1. Field of the Invention
This invention relates generally to the field of devices for protecting the mating plug and socket ends of electrical cords, and more particularly to a protector for protecting the mating plug and socket of connected electrical cords from damage and contamination and which allows quick disconnection of the plug and socket in an isolated chamber.
2. Brief Description of the Prior Art
Electrical cords, such as extension cords, are common in industrial facilities, outdoor construction sites, and manufacturing facilities. Often the mating plug and socket ends of these types of electrical cords are simply connected together and lie, unprotected, on the floor or ground and are subject to being pulled apart accidentally and to being damaged by pedestrian or vehicular traffic or being crushed by piping, beams, tools, etc. The unprotected connection is also be exposed to water, mud, and other contaminants, which may cause injury to personnel and corrosion of the mating components.
In some environments, the sparking or arc caused by pulling the mating plug and socket ends of electrical cords apart can cause an explosion. In some instances, the mating plug and socket ends of electrical cords are tied or otherwise secured together to prevent them from being separated accidentally. Securing the mating plug and socket ends of electrical cords together is not satisfactory, since it is important to be able to quickly break the electrical connection in the event of an emergency. For example, if a machine malfunctions or a worker is caught in a machine.
There are several patents which disclose various protectors and retainers for the mating plug and socket ends of electrical cords. Most of which secure the connection together and prevent the plugs from being pulled apart.
Gartland, Jr., U.S. Pat. No. 4,003,622, Burke, Jr., U.S. Pat. No. 4,721,475, Odbert, U.S. Pat. No. 4,940,424, and Bresko, U.S. Pat. No. 4,998,891 disclose devices for maintaining the male and female plugs of an electrical cord connected together. The device comprises a first cylindrical member which surrounds the male plug and a second cylindrical member which surrounds the female plug. The cylindrical members are secured on the cords behind each plug and one member has protuberances which slide and latch in grooves in the other member to prevent the plugs from being pulled apart.
Gallagher, U.S. Pat. No. 4,169,643 discloses a cylindrical clip for maintaining the male and female plugs of an electrical cord connected together. The clip is a hollow cylindrical housing made in two halves and hinged along one side and provided with latches on the opposite side. The housing surrounds an electrical connection and is latched around the electrical plug connection to prevent the electrical plugs from being pulled apart.
House et al, U.S. Pat. No. 4,643,505 discloses a hinged housing for maintaining the plugs of an extension cord connected together. Washers are installed on the cords behind each plug and each half of the housing has a series of parallel spaced internal grooves which surround and engage the washers to prevent the plugs from being pulled apart.
Ryan, U.S. Pat. No. 4,784,612 discloses an electrical plug holder for maintaining the male and female plugs of an electrical cord connected together. The device comprises a first cylindrical member which surrounds the male plug and a second cylindrical member which surrounds the female plug. The cylindrical members are threadedly secured together by mating helix threads to prevent the plugs from being pulled apart.
Scheffey, Sr., U.S. Pat. No. 5,037,324 discloses a plug and socket retainer for maintaining the plug and socket of an electrical cord connected together. The device comprises a cylindrical housing having a longitudinal slit for receiving the cord and which surrounds the connected plug and socket. The housing is provided with a pair of longitudinal serrated projections. A cover member also having a longitudinal slit is installed on the other electrical cord and provided with slits which receive and engage the serrated projections of the housing to prevent separation and prevent the plugs from being pulled apart.
Koch, U.S. Pat. No. 5,052,939 discloses a cylindrical protector for preventing unauthorized use of an electrical plug. The protector is a hollow cylindrical housing made in two halves and hinged along one side and provided with mating lips on the opposite side. The housing surrounds an electrical connection and is either bolted or locked around the electrical plug connection. The electrical plugs cannot be pulled apart.
The present invention is distinguished over the prior art in general, and these patents in particular by a protector for protecting the mating plug and socket of connected electrical cords from damage and contamination and which allows quick disconnection of the plug and socket in an isolated chamber. The protector has a tubular housing formed of high impact plastic, preferably transparent, which surrounds the mating plug and socket members of connected electrical cords and resilient end plugs which are slidably received on the cords rearwardly of the plug and socket. The end plugs have a longitudinal slit extending radially from a central longitudinal bore and are installed by pressing them laterally onto the cords then sliding them axially on the cords to press them into the open ends of the tubular housing. When pressed into the ends of the housing, the end plugs define a central chamber surrounding the plug and socket connection and form a seal at the opposed ends of the chamber between the housing and the exterior of the cords. The coefficient of friction between the end plugs and interior of the housing is greater than the coefficient of friction between the end plugs and the cords such that the end plugs remain frictionally engaged with the interior of the housing while allowing relative sliding movement between the cords and end plugs. When the cords are pulled apart, the plug and socket separate completely while enclosed in the sealed chamber to isolate any spark or arc and continued axial movement pulls the end plugs from the ends of the housing.